Integrate RNS Registry into EnsController

[jonathansmirnoff]

Explanation

This PR adds the RNS Registry address to the EnsController package. This enhancement enables the resolution of .rsk domains in the Rootstock-compatible version of MetaMask.

Why:

By including the RNS Registry address, users will be able to resolve human-readable domain names (e.g., alice.rsk) directly in MetaMask when interacting with dApps built on Rootstock. This improves the user experience and provides native support for domain name resolution within the Rootstock ecosystem.

Note:

We are aware that additional changes are required in MetaMask to fully support RNS resolution. However, this PR represents the first step toward enabling complete RNS integration within the wallet.

Further Reading:

• Learn more about RNS and how it works in the Rootstock ecosystem:
  Rootstock - RNS Overview

• General information about Rootstock:
  Rootstock Developer Portal

Checklist

• [X] I've updated the test suite for new or updated code as appropriate
• [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• [ ] I've communicated my changes to consumers by updating changelogs for packages I've changed, highlighting breaking changes as necessary
• [ ] I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes